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by razingeden 145 days ago
it’d depend on what exactly is failing there.

File missing:

if [ ! -f /tmp/file ]; then exit 1 fi

File doesn’t contain 100 lines:

COUNT=`cat /tmp/file |wc -l` if [ $COUNT -lt "100"]; then exit 1 fi

File doesn’t contain a known header or record :

HEADER=`egrep -c SOME_CSV_VALUE /tmp/file` if [ $HEADER -eq "0"]; then exit 1 fi

any of those could be things like MySQL cli query or a wget call to a webserver.

generally, I have one long script that validates a combination of these and as it runs through the script I echo the HTML, meta refresh tag. My table, my table row, then each “if” case appends a <TD> </TD></TR>with “else” statements adding a red or a green cell into an HTML file as it goes down the list.

That way if I have say, 50-100 critical things that run every morning I have a visual dashboard when one screws up.

As far as I know this is still in use 14 years after deployed. It’s in all the stuff that starts an options exchange every day.

And then I left behind another one at a telco that checks all their radius servers and radius partners and pops a cell red when one isn’t responding to auth requests and I “think” they are using some form of it. Other than now solar winds hooks into those exit codes and they don’t really care about the html page.